Rotating valve for separating high and low pressure exhaust gases



Aug. 17, 1954 ROTATI AND Filed Oct. 29, 1952 K.V.ANDERSON VALVE FORSEPARATING HIGH PRESSURE EXHAUST GASES 3 Sheets-Sheet l KARL V.ANDERSON.

INVENTOR ATTORNEY Aug. 17, 1954 K. v. ANDERSON 2,686,398

ROTATING VALVE FOR SEPARATING HIGH AND LOW PRESSURE EXHAUST GASES FiledOct. 29, 1952 3 Sheets-Sheet 2 N o :0 IO a: r 3 N N l i 6 Ill 3 :I

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I 0 a I N is (D N v- I I i :a "'o l I N I I I i as i l E 1" KARL V.ANDERSON.

INVENTOR ATTORNEY Aug. 17, 1954 Filed Oct. 29, 1952 ROTATING VALVE FORSEPARATING HIGH AND LOW PRESSURE EXHAUST GASES K v ANDERSON 2,686,398

3 Sheets-Sheet 3 I I CYLINDER PRESSURE l l l 50 i V IO W XY B.D.C.T.D.C. B .D.C T.D.C B.D.C.

CRANK ANGLE EXHAUST HIGH PRESSURE A EXHAUST LOW PRE$SURE FIG.3.

KARL V. ANDERSON.

INVENTOR ATTO RN EY Patented Aug. 17, 1954 ROTATING VALVE FOR SEPARATING HIGH AND LOW PRESSURE EXHAUST GASES Karl V. Anderson, Schenectady, N.Y., assignor to American Locomotive Company, New York, N. Y., acorporation of New York Application October 29, 1952, Serial No. 317,515

8 Claims.

This invention relates to exhaust manifolds for internal combustionengines, and particularly to that class of manifolds which conducts theexhaust gases to the turbine Wheel of a turbocharger.

In conventional manifolds, the risers from the engine cylindersgenerally open into a single or multiple pipe system which permits freecommunication among all of the risers or at least among several of them.Such an arrangement is objectionable since the exhaust gases collectedin the manifold from all the cylinders present a back pressure to eachexhausting cylinder which prevents proper scavenging thereof.Furthermore, pressure waves are generated by the exhaust gases in themanifold which are reflected back through the risers to the enginecylinders to interfere with scavenging,

The main object of this invention, therefore, is to provide an exhaustmanifold for a multicylinder internal combustion engine which minimizesback pressure and prevents reflected waves from interfering with thescavenging operation of all of the cylinders. Another object is toprovide such a manifold which, in addition to achieving the foregoingresults, provides for the utilization of all the available energy of theexhaust puff to drive the supercharger turbine.

Another object is to provide such a manifold having two separateconductors leading the exhaust gases to the turbine, said conductorsbeing controlled by a valve so that the leading or high pressure portionof each exhaust puff is received by one conductor and the trailing orlow pressure portion of the puff is received by the other conductor,such valve being so designed that the exhaust gases from each of thecylinders is isolated from the other cylinders so as not to interferewith the scavenging operation of such other cylinders. Still anotherobject is to provide such a manifold which includes a timed rotary valveadapted (a) to distribute the first or high pressure portion of eachexhaust puff into one conductor in such manner that back pressure andreflected waves are prevented from reaching any of the other powercylinders, and (b) to distribute the later or low pressure portion ofthe puff free of the high pressure effects into a second conductor, bothconductors being adapted to supply pressure to the supercharger turbine.Still another object is to provide such a manifold, which achieves theobjects last mentioned, and also allows a portion of the scavenging airto pass out of the power cylinder into the low pressure conductor toimpinge upon the turbins to cool it.

Other and further objects of the present invention will be apparent fromthe following description, the accompanying drawings, and the appendedclaims.

In the drawings:

Fig. l is a cross section through the manifold taken on line l-l of Fig.2.

Fig. 2 is an elevation cross section taken on line 2-2 of Fig. 1; and,

Fig. 3 is a graph of the cylinder pressure illustrating the valveoperation.

Referring now to Fig. 1, the manifold of the invention is illustrated asapplicable to a V-type four-stroke cycle engine having four powercylinders. It may, however, be designed for inline engines, or fortwo-stroke cycle engines, or for engines having more or fewer cylinders,The manifold comprises a cylindrical housing, generally indicated as l0,which extends substantially the full length of the engine and has abottom flange H at its foot for securement to the flanged exhaust risersl2 of the engine. Extending upwardly from the flanges into the housingare a plurality of passages l3 leading into a cylindrical centercollector M which extends substantially the full length of theapparatus. Secured to the opposite sides of the collector and extendingthe full length thereof are two gas conductors l5 and I6 which arearcuate in cross section, as bestshown in Fig. 1. In each of the lateralsides of the wall of the collector I4 is a series of four longitudinallyspaced ports, one series ll providing communication between thecollector and conductor I?) at four places and the other series 18providing communication between the collector and conductor 16 at fourplaces. Each of the ports is is disposed approximately opposite one ofthe ports ll. The ports is are larger than ports i7, havingapproximately twice their cross sectional area in the embodiment shown.

Arranged within the collector I 4 is a rotary distributing valve,generally indicated as i .9, comprising a central cylindrical body 20having spaced cup portions 2! thereon (see Fig. 2). The outside Wall 22of each cup portion has a close rotary sliding fit with the collector itso that the valve forms four separate compartments 22a in the collectorM. Valve i9 is mounted at its ends in bearings 23 and 24 and is providedwith a series of four longitudinally spaced openings 25. Each of theopenings 25 is so arranged that, as the valve rotates, it is broughtprogressively into registration with a port ii and a port i8. Openings25 are disposed angularly at from each other around the periphery ofvalve 39.

Obviously engines of other than four cylinders would require differentangular displacement of the openings 25. Disposed within valve body 20and extending its entire length is a driving shaft 2E, the left end ofwhich, as viewed in Fig. 2, is threaded for the reception of nut 21 andthe right end of which is formed with a reduced por-- tion 28 upon whichis mounted a bevel gear 29. Shaft 25 is conventionally secured to thebody 28 by means not shown to rotatably drive the latter. Nut 39, by aconventional key, maintains the gear in mounted position. Meshed withgear 29 is a second bevel gear 3| mounted upon shaft 32 which is rotatedby the engine cam shaft by connecting means not shown. Shaft 32 is sogeared to the cam shaft that the R. P. M. of valve I9 is one half the R.P. M. of the engine crankshaft. Hence, in a four-stroke cycle engine,the valve openings 25 are brought into registration with each of theports I! and I8 once for each exhaust stroke. Obvious changes inconstruction may be made to provide for valve rotation equal to enginecrankshaft speed in case the manifold should be applied to a two-strokecycle engine. Upon the forward end of the housing III (the left end asviewed in Fig. 2), there is mounted a header 35 having two ducts 36 and3-1, arcuate in cross section, which register with conductors l6 and Irespectively to connect the conductors with nozzles 38 and 39. Thesenozzles each include substantially half the turbine circumference andare separated from one another. Means are thus provided to direct theexhaust gases from conductors I5 and I6 into impingement upon the blades56 of the turbine 34 which serves to actuate the supercharger. Thejacket 4 l, which is defined by housing wall 42, the outer walls 43 and44 of conductors I6 and I5, and by wall portion 45 of collector l4carries cooling water which is supplied through inlet pipes 46 and whichis drawn off by outlet pipes 41. Such cooling means is resorted to inorder to maintain the wall of collector H! at a temperature low enoughto prevent seizure of the rotating distributing valve l9. Referringagain to Fig. 1, it is seen that the valve is so timed that the exhaustpuff from the engine cylinder passes up riser l2, through passage I3into the compartment 22a, and into the cup portion 2| of thedistributing valve [9. The first or high pressure portion of the puffescapes into conductor l5 since opening 25 and port H are incommunication. The valve rotates clockwise, as viewed in Fig. 1, and itsspeed of rotation is such that the pufi is cut off after its first orhigh pressure portion enters conductor !5. Then, as the valve continuesits rotation, opening 25 overlaps port i8 and the remaining or lowpressure portion of the puff escapes into conductor l6 over a longerperiod of time. Also, by such rotation, the valve cuts off passage ofgas into conductor l5. The construction of the valve, including the cupportion 2|, is such that each puff is segregated from communication withthe other risers and hence the cylinders. Back pressure on the othercylinders of the engine is thus avoided. A slight simultaneous overlapof opening 25 with both ports I! and I8 is preferred to avoid pressurebuild-up in the compartments 22a. That is, opening 25 registers withport l8 slightly before it moves out of registry with port H.

In Fig. 3 there is shown by the solid line a pressure curve for a singlecylinder of a four-stroke cycle multi-cylinder engine equipped with amanifold of the invention, such curve being plotted to show the cylinderpressure in relation to the crank angle. Hereafter this curve isreferred to as the invention curve. Superimposed on this invention curveis the pressure curve for a similar cylinder equipped with aconventional multipiped manifold. This curve is indicated by the dottedline, except where it coincides with the solid line of the inventioncurve. Hereafter this curve is referred to as the conventional curve."In the first quarter section of the chart, the invention curve shows thepressure rise which takes place during the compression stroke. In thesecond quarter section of the chart, the curve indicates that thepressure continues to rise after the piston has passed top dead centerand begins the power stroke. The piston is now descending and thecombustion space is expanding so that the pressure drops, as indicated.At point T on the invention curve the engine exhaust valve opens, andthe rotary valve l9 brings opening 25 into communication with port H tolead the exhaust gases into high pressure conductor l5. It should behere noted that the slope of the curve at this point becomes greater,indicating an increased rate of pressure drop because of the opening ofthe exhaust valve. At point U on the curve, which is in close proximityto the bottom dead center position of the crank, valve 19 brings opening25 into communication with port l8 to start exhausting the trailingportion of the exhaust puff into low pressure conductor [5. At point Von the curve valve i9 moves opening 25 out of communication with portIT. The overlap of opening 25 in relation to ports I? and i8 isindicated on the curve as the distance UV. When port I! is closed, theleading or high pressure portion of the exhaust puff is trapped inconductor !5 to supply the turbine and is of course isolated from thepower cylinder. The invention curve indicates the low pressure in thecylinder. The pressure continues to drop until the engine inlet valveopens for the admission of scavenging air from the supercharger. Thisoccurrence is indicated at point W on the invention curve. Since theexhaust valve is still open to permit the scavenging operation, thescavenging air passes directly through the cylinder. The invention curvethen levels off to indicate such condition. In the fourth quartersection, X indicates the point at which the engine exhaust valve closesand at which the engine cylinder pressure begins to rise during theintake stroke. Further on the curve in the fourth quarter, Y indicatesthe point at which the opening 25 is moved out of communication withport B8 to close off the low pressure conductor It. It should be hereobserved that the distance XY on the curve indi cates an interval inwhich the scavenging air passes through the cylinder into low pressureconductor [6. This effects a cooling effect upon the turbine. Theremainder of the curve in the fourth quarter section indicates acontinuance of the gradual rise in pressure as the cylinder is chargedon its intake stroke.

The conventional curve indicates the pressure in the cylinder equippedwith a conventional multi-piped manifold and coincides with theinvention curve to point T where the exhaust valve opens. Then theconventional curve, as indicated by the dotted line portion, becomessteeper than the invention curve because the turbine equipped with thepresent invention is designed to maintain a higher pressure in conductorl5 than in the conventional manifold pipe. The conventional curverejoins the solid line curve at point Z which is close to point W andfollows the 5. same course thereafter throughout the cycle. The spacebetween the two curves in the interval TZ represents the increase in theenergy extracted from the exhaust by the present invention.

Thus, the present manifold invention, by the unique separation of eachexhaust puff into high and low pressure portions, provides for theextraction of more energy and the diminution of back pressure on thecylinders during scavenging. The cylinders then operate with nointerference from each other. The invention, therefore, provides for thegeneration of more horsepower per unit of fuel.

While there has been hereinbefore described an approved embodiment ofuhiS invention, it will be understood that many and various changes andmodifications in form, arrangement of parts and details or" constructionthereof may be made without departing from the spirit of the invention,and that all such changes and modifications as fall within the scope ofthe appended claims are contemplated as part of this invention.

What I claim is:

1. [in exhaust manifold for a turbo-supercharged multi-cylinder internalcombustion encomprising a collector for receiving the exhaust puffs fromeach cylinder, a valve within the collector compartmented to segregatethe exhaust puiis of one cylinder from the exhaust pufis of the othercylinders, independent high and low pressure conductors intermittentlyin communication with the collector through said valve, and means tooperate said valve to divide each segregated puif into predeterminedhigh and low pressure portions and direct said portions into thecorresponding conductors to a point of use.

2. An exhaust manifold for a turbo-supercharged multi-cylinder internalcombustion engine comprising a collector for receiving the exhaust puffsfrom each cylinder, a rotary valve within the collector compartmented tosegregate the exhaust pulls of one cylinder from the exhaust puffs ofthe other cylinders, independent high and low pressure conductorsintermittently in communication with the collector through said rotaryvalve, and means to rotate said valve to divide each segregated puffinto predetermined high and low pressure portions and direct saidportions into the corresponding conductors to a point or" use.

3. An exhaust manifold for a turbo-supercharged multi-cylinder internalcombustion engine comprising a cylindrical collector for receiving theexhaust puffs from each cylinder, a rotary valve within the collectorcompartmented to segr te the exhaust puiifs of one cylinder Trom theexhaust puffs of the other cylinders, independent high and low pressureconductors adjacent said collector, ports in said valve to permitintermittent sequential communication between the collector andconductors, and means to rotate said valve, whereby upon said sequentialcommunication a predetermined portion of each puff is supplied to saidhigh and low pressure conductors successively, said conductors thenconducting said predeterniined portions to a point of use.

4-. An exhaust manifold for a turbo-superchar ed multi-cylinder internalcombustion engine comprising a collector, separate passages to transmitthe exhaust gases from each engine cylinder to the collector, twoconductors to receive the exhaust gases from the collector and transmitthem to the supercharger turbine, ports in the collector to permit thepassage of exhaust gases therefrom into one conductor, ports in thecollector to permit the passage of exhaust gases therefrom into theother conductor, and a rotary valve divided into compartments each ofwhich separately receives the exhaust puffs from said separate passages,means to rotate said valve, said valve having an opening in eachcompartment adapted to register with a port in the first conductor andthen with a port in the second conductor to transmit predeterminedportions of the exhaust gases to the respective conductors.

5. An exhaust manifold for a turbo-supercharged multi-cylinder internalcombustion engine comprising a collector, a rotary valve in thecollector divided into a number of compartments equal to the number ofengine cylinders, means to admit exhaust gases into each valvecompartment, separate passages adapted to separately lead the exhaustgases from each engine cylinder into a valve compartment, an opening ineach valve compartment to permit the escape of exhaust gases therefrom,two conductors adjacent the collector to lead exhaust gases to a pointof use, a series of ports in the first of the two conductors spaced sothat each port registers with a valve compartment opening on each valverotation, a series of ports in the second of the conductors likewisespaced so that each port registers with a valve compartment opening oneach valve rotation, and means to rotate the valve in timed relation tothe firing of the cylinders, the arrangement of the elements being suchthat each cylinder exhaust pun" passes through a separate passage into avalve compartment whence a predetermined portion thereof passes througha port into one conductor and then a second predetermined portionthereof passes through a port into the other conductor.

6. An exhaust manifold for a turbmsupercharged multi-cylinder internalcombustion engine comprising a cylindrical collector, separate passagesadapted to separately lead the exhaust gases from each engine cylinderto the collector, two separate conductors to receive the exhaust gasesfrom the collector to transmit them to the supercharger turbine, arotary valve in the collector divided into a number of compartmentsequal to the number of engine cylinders, each of the compartments beingadapted to receive the exhaust gases from a separate passage, a seriesof ports in the first of said conductors, each port being disposedopposite a valve compartment, a series of ports in the second conductoreach port being disposed opposite a valve compartment, and a series ofopenings in the valve, one for each compartment, the arrangement of saidports and openings being such that as the valve rotates, each exhaustpuff proceeding from an engine cylinder into the collector is divided bythe valve so that a predetermined portion thereof passes through a valveopening and a conductor port into one conductor and a secondpredetermined portion subsequently passes Trough said valv opening and aconductor port into the other conductor.

7. An exhaust manifold for a turbo-supercharged multi-cylinderfour-stroke cycle internal combustion engine comprising a collector, arotary valve in the collector divided into a number of compartmentsequal to the number of engine cylinders, separate passages adapted toseparately lead the exhaust puffs from each engine cylinder into a valvecompartment, an opening in each compartment to permit the escape ofexhaust puffs therefrom, two conductors adjacent the collector to leadexhaust puffs to a point of use, a series of ports in the first of thetwo conductors spaced so that each port registers with an opening in avalve compartment on each valve rotation, a series of ports in thesecond of the conductors likewise spaced so that on each valve rotationeach port registers with an opening in a valve compartment, thedimensions of the latter opening being such that its registration withsuch ports at one time overlap, and means to rotate the valve in timedrelation to the firing of the engine cylinders so that predeterminedportions of each exhaust pufi are supplied to the conductorssuccessively.

8. An exhaust manifold for a turbosupercharged multi-cylinderfour-stroke cycle internal combustion engin comprising a collector,independent means to conduct the exhaust pufis from each cylinder to thecollector, a rotary valve within the collector, said valve having acompartment for each cylinder, independent high and low pressureconductors adjacent the collector, means to rotate the valve at one-halfengine speed, means in the valve and the conductors to permit successivecommunication therebetween upon rotation of the valve whereby theexhaust puffs from each cylinder are divided into predetermined high andlow pressure portions in their respective conductors and the timing ofvalve rotation permits the high pressure portion of the cylinder exhaustpuff to be out of communication with its cylinder when said cylinder isscavenging.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,765,716 Curtis et a1 June 24, 1930 2,423,602 MagdeburgerJuly 8, 1947 FOREIGN PATENTS Number Country Date 354,242 Great BritainJuly 30, 1931 392,698 France Oct. 3, 1908 470,042 Germany Jan. 4, 1929212,701 Switzerland June 16, 1941

